ANALYTICAL APPROACH TO THE PENNE’S BIOHEAT EQUATION FOR THE EVALUATION OF TEMPERATURE FOR DEEP SEATED TISSUES

2021 ◽  
Vol 10 (7) ◽  
pp. 2957-2976
Author(s):  
A. Akpolile ◽  
E. Mokobia ◽  
J. Ikubor

In clinical practice, body temperature is an acclaimed indicator for diagnosis and treatments amongst other follow - ups. This work studied the temperature distribution in deep-seated tissues using Penne’s bio-heat equation (PBE). The analytical solution of the PBE was formulated using the separation of variable technique. The resulting solution gives an expression for tissue temperature in organs that are located inside the body. This revealed that the tissue temperature is subject to changes in tissue thickness, the distance of tissue from the skin surface and other thermal properties of tissues under consideration.

1991 ◽  
Vol 70 (6) ◽  
pp. 2682-2690 ◽  
Author(s):  
M. B. Ducharme ◽  
P. Tikuisis

The effective thermal conductivities of the skin + subcutaneous (keff skin + fat) and muscle (keff muscle) tissues of the human forearm at thermal steady state during immersion in water at temperatures (Tw) ranging from 15 to 36 degrees C were determined. Tissue temperature (Tt) was continuously monitored by a calibrated multicouple probe during a 3-h immersion of the resting forearm. Tt was measured every 5 mm from the longitudinal axis of the forearm (determined from computed-tomography scanning) to the skin surface. Skin temperature (Tsk), heat loss (Hsk), and blood flow (Q) of the forearm, as well as rectal temperature (Tre) and arterial blood temperature at the brachial artery (Tbla), were measured during the experiments. When the keff values were calculated from the finite-element (FE) solution of the bioheat equation, keff skin + fat ranged from 0.28 +/- 0.03 to 0.73 +/- 0.14 W.degrees C-1.m-1 and keff muscle varied between 0.56 +/- 0.05 and 1.91 +/- 0.19 W.degrees C-1.m-1 from 15 to 36 degrees C. The values of keff skin + fat and keff muscle, calculated from the FE solution for Tw less than or equal to 30 degrees C, were not different from the average in vitro values obtained from the literature. The keff values of the forearm tissues were linearly related (r = 0.80, P less than 0.001) to Q for Tw greater than or equal to 30 degrees C. It was found that the muscle tissue could account for 92 +/- 1% of the total forearm insulation during immersion in water between 15 and 36 degrees C.


Author(s):  
Titilayo Dorothy Odetola ◽  
Olusola Oluwasola ◽  
Christoph Pimmer ◽  
Oluwafemi Dipeolu ◽  
Samson Oluwayemi Akande ◽  
...  

The “disconnect” between the body of knowledge acquired in classroom settings and the application of this knowledge in clinical practice is one of the main reasons for professional fear, anxiety and feelings of incompetence among freshly graduated nurses. While the phenomenon of the theory-to-practice gap has been researched quite extensively in high-income country settings much less is known about nursing students’ experiences in a developing country context. To rectify this shortcoming, the qualitative study investigated the experiences of nursing students in their attempt to apply what they learn in classrooms in clinical learning contexts in seven sites in Nigeria. Thematic content analysis was used to analyse data gained from eight focus group discussions (n = 80) with the students. The findings reveal a multifaceted theory-practice gap which plays out along four tensions: (1) procedural, i.e. the difference between practices from education institutions and the ones enacted in clinical wards – and contradictions that emerge even within one clinical setting; (2) political, i.e. conflicts that arise between students and clinical staff, especially personnel with a lower qualification profile than the degree that students pursue; (3) material, i.e. the disconnect between contemporary instruments and equipment available in schools and the lack thereof in clinical settings; and (4) temporal, i.e. restricted opportunities for supervised practice owing to time constraints in clinical settings in which education tends to be undervalued. Many of these aspects are linked to and aggravated by infrastructural limitations, which are typical for the setting of a developing country. Nursing students need to be prepared regarding how to deal with the identified procedural, political, material and temporal tensions before and while being immersed in clinical practice, and, in so doing, they need to be supported by educationally better qualified clinical staff.


2019 ◽  
Vol 31 (3) ◽  
pp. 251-256

Cirrhosis of liver is one of the common medical problem in daily clinical practice and one of the leading causes of morbidity and mortality. Zinc is an essential trace elements for human and plays in many biological roles in the body. Among them, zinc deficiency is thought to be involved in metabolism of ammonia and causes hyperammonia that worsen hepatic encephalopathy. This study aimed to find out the severity of cirrhosis of liver was by Child Turcotte Pugh score and to investigate the associations between serum zinc level and severity of cirrhosis. A hospital-based cross-sectional descriptive study was performed on 78 patients with different underlying causes of cirrhosis of liver at the Medical Units of Yangon General Hospital and Yangon Specialty Hospital. Among the study population, Child grade A was found to be 28.21%, Child grade B was 30.77% and Child grade C was 41.03%. Regarding result of serum zinc level, 62.8% were low level, 28.2% were within normal level and 8.9% were high level. Mean value of serum zinc level in grade A was 0.68 mg/l, grade B was 0.54 mg/l and grade C was 0.48 mg/l (p=0.00). It was found out that there was a high prevalence of zinc deficiency in severe cirrhotic patients. The zinc level was significantly lowest among patients with Child-Pugh C as compare to those with Child-Pugh B and C. Severity of zinc deficiency should be requested for supplementation therapy in cirrhotic patients as to prevent complications such as hepatic encephalopathy, hepatocellular carcinoma and liver failure. Screening for zinc deficiency may need in these patients with more advanced cirrhosis because it seems to be a marker of advanced liver disease and it can be deducted that awareness of serum zinc level among cirrhotic patients is very important in clinical practice.


2021 ◽  
Vol 10 (2) ◽  
pp. 228
Author(s):  
Tomonari Kinoshita ◽  
Taichiro Goto

Despite complete resection, cancer recurrence frequently occurs in clinical practice. This indicates that cancer cells had already metastasized from their organ of origin at the time of resection or had circulated throughout the body via the lymphatic and vascular systems. To obtain this potential for metastasis, cancer cells must undergo essential and intrinsic processes that are supported by the tumor microenvironment. Cancer-associated inflammation may be engaged in cancer development, progression, and metastasis. Despite numerous reports detailing the interplays between cancer and its microenvironment via the inflammatory network, the status of cancer-associated inflammation remains difficult to recognize in clinical settings. In the current paper, we reviewed clinical reports on the relevance between inflammation and cancer recurrence after surgical resection, focusing on inflammatory indicators and cancer recurrence predictors according to cancer type and clinical indicators.


1999 ◽  
Vol 202 (21) ◽  
pp. 3021-3028 ◽  
Author(s):  
T.C. Hoffman ◽  
G.E. Walsberg

We tested the hypothesis that birds can rapidly change the conductance of water vapor at the skin surface in response to a changing need for evaporative heat loss. Mourning doves (Zenaida macroura) were placed in a two-compartment chamber separating the head from the rest of the body. The rate of cutaneous evaporation was measured in response to dry ventilatory inflow at three ambient temperatures and in response to vapor-saturated ventilatory inflow at two ambient temperatures. At 35 degrees C, cutaneous evaporation increased by 72 % when evaporative water loss from the mouth was prevented, but no increase was observed at 45 degrees C. For both dry and vapor-saturated treatments, cutaneous evaporation increased significantly with increased ambient temperature. Changes in skin temperature made only a minor contribution to any observed increase in cutaneous evaporation. This indicates that Z. macroura can effect rapid adjustment of evaporative conductance at the skin in response to acute change in thermoregulatory demand.


Author(s):  
Elena Sergeevna Ilyina ◽  
Natal’a Valer’evna Filippova ◽  
Yulia Borisovna Barylnik

Pharmacogenetics is a relatively new scientific discipline, which is currently the main tool in personalized medicine. The aim of research in this area is to identify significant genetic markers for the introduction of their accounting in routine clinical practice. Generalization of data on the patient’s phenotype should be the key to predicting the pharmacokinetics and pharmacodynamics of the drug in the body. A personalized approach based on pharmacogenetic research data in psychiatry is extremely relevant due to the high social and budgetary costs of treating mental disorders around the world. Currently, there are data on the pharmacogenetics of most modern antidepressants, however, conducting such studies in patients with depressive disorders in most cases is impossible for implementation in routine clinical practice due to the impossibility of conducting the test in the laboratory of medical organizations and the lack of specialists competent in the clinical interpretation of the results of pharmacogenetic testing.


2018 ◽  
Vol 48 (6) ◽  
pp. 869-890
Author(s):  
Sophie Merit Müller

Various specialist cultures configure bodies as complex technological devices. We know little about how exactly this is done. I focus on one of these cultures, classical ballet, to praxeologically reconstruct the conceptual, situational and material configuration of bodies as particular instruments. The technologization of the body is closely intertwined with the scientification of the practice – its ladenness with scientific knowledge about the body and an elaborate apparatus for the production of bodies. When anatomical knowledge and didactics intertwine in ballet class, this facilitates an opening of the black box ‘body’ for technical improvement. ‘A body’ becomes a plurality of (in this case, anatomically distinguished) actants. This distributed corporeality suggests that ‘the body’ is an assemblage that becomes apparent as such in moments of its modification. The empirical case as well as the analytical approach here give reason to reconsider the distinction between humans and non-humans that still prevails in actor-network theory and elsewhere.


1956 ◽  
Vol 188 (1) ◽  
pp. 103-112 ◽  
Author(s):  
Knut Schmidt-Nielsen ◽  
Bodil Schmidt-Nielsen ◽  
S. A. Jarnum ◽  
T. R. Houpt

The rectal temperature of normal healthy camels at rest may vary from about 34°C to more than 40°C. Diurnal variations in the winter are usually in the order of 2°C. In summer the diurnal variations in the camel deprived of drinking water may exceed 6°C, but in animals with free access to water the variations are similar to those found in the winter. The variations in temperature are of great significance in water conservation in two ways. a) The increase in body temperature means that heat is stored in the body instead of being dissipated by evaporation of water. At night the excess heat can be given off without expenditure of water. b) The high body temperature means that heat gain from the hot environment is reduced because the temperature gradient is reduced. The effect of the increased body temperature on heat gain from the environment has been calculated from data on water expenditure. These calculations show that under the given conditions the variations in body temperature effect a considerable economy of water expenditure. The evaporative heat regulation in the camel seems to rest exclusively on evaporation from the skin surface (sweating), and there is no apparent increase in respiratory rate or panting connected with heat regulation. The evaporation from isolated skin areas increases linearly with increased heat load. The critical temperature at which the increase sets in is around 35°C. The fur of the camel is an efficient barrier against heat gain from the environment. Water expenditure is increased in camels that have been shorn.


Author(s):  
Abinand Manorama ◽  
Tamara Reid Bush

Pressure ulcers have been a concern in healthcare settings, with more than 50% of bedridden or wheelchair-bound patients being affected [1]. Pressure ulcers typically occur on a region of the body that experiences forces from an external structure (e.g. bed, wheelchair). Researchers believe that such forces cause a decrease in blood flow, which results in tissue necrosis, causing pressure ulcers [2].


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